diff --git a/SConstruct b/SConstruct
index e2f21d0..0030bd5 100644
--- a/SConstruct
+++ b/SConstruct
@@ -254,6 +254,7 @@
                    extent_writer.cc
                    filesystem_copier_action.cc
                    filesystem_iterator.cc
+                   file_descriptor.cc
                    file_writer.cc
                    flimflam_proxy.cc
                    full_update_generator.cc